A Greek Gypsy couple, accused of kidnapping a little girl, was given the girl by a Bulgarian Gypsy and adopted her "in a non-legal way," the couple's lawyer told ABC News today.

A police source told ABC News that the girl, known only as Maria, was one of four children found with the couple, including two other girls and a boy. The police source said the couple had registered 14 children for welfare benefits, but it was not clear whether the other children existed.

DNA tests have shown that adults were not the parents of Maria. It's not known if the three other kids were the natural children of the couple.

Marietta Palavrasa, the couple's defense lawyer, said the girl's mother was a Bulgarian Gypsy who lived in the Thessalia region of Greece for many years.

"My clients never talked about Maria's biological father. They think he was in prison," Palavrasa said. "The Bulgarian woman gave my clients the child. My clients adopted her in non-legal way, but they cared for her as if she were their child."

The case has swamped the police with phone calls.

"We received thousands of calls from all over the world and we are investigating this case trying to find the biological mother (of Maria)," the source said.

Maria was initially described as being about 4, but officials now believe she could be as old as 6.

Police found the girl living in a Gypsy encampment near the city of Farsala during a nationwide crackdown on Gypsies, also known as Roma, believed to be engaged in illegal activity.

A prosecutor, who accompanied police, noticed the girl, whose blonde hair and blue eyes set her apart from the rest of the darker skinned members of that community.

The couple Christos Salis, 39, and his partner who was carrying two identification cards and is either Eleftheria Dimopoulou, 40, or Selini Sali, 41, have been charged with kidnapping a minor and falsifying documents. Salis was also charged with possession of drugs and firearms.

Following Maria's discovery, Interpol released an international appeal for information about her parents. Thousands of tips and messages of support have reached "Smile for the Child," the charity currently taking care of the girl.